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About glulam

Photo: Christian Ljung

Structure

Glulam (glued laminated timber) comprises a number of wood laminates glued together. The fibres in the laminates run parallel to the length of the piece. In straight glulam products, the laminates are 45 mm thick. For curved products, the thickness is less, generally 33 mm.

Glulam is a construction material that comes in a range of strength classes. The manufacturing standard for the Swedish market is strength class GL30. Some glulam beams are made by splitting glulam beams of class GL30 to create split timber beams, which then have a strength class of GL28.

Glulam sets no limits on the potential for wood construction techniques.

Glulam beams are made with laminates of a higher strength class on the bottom and top, where the maximum tensile and compressive stresses occur. The rest of the cross-section, where the stresses are lower, uses laminates of a lower strength class. The manufacturing method is called combined glulam and is usually indicated with the letter c after the strength class designation. This allows more efficient use of material compared with only using wood of the same strength class.

Alternatively, glulam may be made with laminates of the same high strength class throughout, and this is represented with an h for homogeneous after the strength class designation. Glulam is available in a large number of dimensions. Read more under Range.

Custom manufacture

Where large spans, loads or other circumstances define the design, glulam is made to the drawings and accompanying specifications as required, in consultation with the glulam manufacturer’s structural engineers. Custom-made glulam elements are available in practically any shape and dimension to meet the architect’s vision and other parameters.

Examples of common custom glulam products include curved beams, pitched beams, portals and arches. Contact one of the glulam manufacturers for more information.

Glulam has a good environmental profile in manufacture and use.Photo: Johan Ardefors.

Why glulam?

Strength – Glulam is one of the strongest construction materials in relation to its weight.

Environment – The raw material is renewable. The glulam can be re-used or recycled.

Aesthetic value – Glulam is a naturally attractive product that people have a strong emotional connection with.

Energy – Energy use in glulam manufacture is very low compared with other construction materials.

About glulam

SWEDISH WOOD is the Swedish glulam manufacturers’ secretariat for technical information and development. The operation to develop the field and distribute information began in the 1970s, with a focus on:

supporting technical and scientific research and product development in the field of wood construction

contributing to the training and education of engineers and researchers in the field of wood construction

helping to raise awareness of the methods and opportunities available within wood construction.

This work is managed by Swedish Wood, a department within the Swedish Forest Industries Federation. Glulam sales are not part of the operational remit. For sales enquiries, please contact the manufacturers directly.

Swedish Wood’s aim is to increase the size and value of the market for Swedish wood and wood products in construction, interior design and packaging. Through inspiration, information and education, we promote wood as a competitive, renewable, versatile and natural material.
Swedish Wood represents the Swedish sawmill industry and is part of the Swedish Forest Industries Federation.